Protected grate block for stokers



Dec. 31, 1929. l. A. TAYLOR 1,741,744

PROTECTED GRATE'BLOCK FOR STOKERS Filed July 9, 1924 2 Sheets-Sheet l QTTOB/VLY Dec. 31, 1929. I I. A. TAYLOR I 1,741,744

PROTECTED GRATE BLOCK FOR STOKERS Filegi July 9, 1924 2 Sheets-Sheet 2 //vy NTOR /R V/NE H. Ignore.

Patented Dec. 31, 1929 I smith .sT

IRVING ALBERT Em r-non, or WORGE'STE-R, 'ivrhs'snfinfs nr rs, AS S IG NTO R' o 'n-I nY "-s'ToKEn CQRRQRA'TZON, or wane-Esme, MAssnoHUsETTs, ,A ICOQPJOBAKTIFOH or M ns- 'SiA'CHlISETTS rjno'i noi ii ,GRKTE {-Bnoox ron stones-s application .-fi1ed July-. 9,

invention ,grelates to gstokers end more p rticularly to the grate bl-k. construeti Q fi undered S ke A tQ Q TJ fithe ty'pe shown in the patent to fRi'l-ey, ;-No. ;1 ,090,6'5l ,of rMe-reh' 17, 1914, has tuyere walls between retorts th-ro gh which coal is ifecl by a, vsuitable Era-tn mechae nis n. These tuyere wallsoomprise twoinned deb rs meun edl-sidefby Side-for alterntte ;-reci-prooa;tion in a horizontal jdirecimlyan gre ock s1 ppoited .in a stepli-k v o ma fon o rthe'se is de bars. T e gr blocks are provided with small tuyere openngi r mm ating with l rge pas g within the iblock th ough which ai is ed- Initted .=to ti rfuel lo'ed. it has been found that the openation of sueh a furneoe, the nose .or fuel rsir-pp(gr-ting portions of (these s e Fb1Q kS I1E t bu n Q and h o e t eense a cha nge the ;-s-ize of ;the -tnyere pe ing -refin r ea a h per tion of t urna s :It is accordingly; thegpringieobj eet of my i invention to 'overeome {this d'ifiio il ty and 5130 p e id e mpro e se a -i e scons ru i whishw 11. (bur m y adi y e d whioh wilLreina-in comparatively; eooll nder Howe l-op a n 'Qondi i and t us ema n efiicient throughout a long period; of servioe.

It is a further object oflm invention to provide a tuye're block which isi so-shaped that the air hioh issues through the tuyere' may, he oausedv to travense a -,circuitous 'path in, Contact ,with; the under ,1 side; ofrthe fblQCk face of lts nose or fuel supportmg portion which 1 t ch g and ashes; nd o Another (ObjOQlZ; of ny invention 5 is. t0-,pro-- ide a grate ,blocgkiconstrnction ,Which will. automatically oateh -and retai a hes-9n surface and so aprovicleen efl'eetive heat insulating coating thereon. V

With these and other :objects View as Will begapperentto one skilled inQthe art,- my

invention resides in the combination of parts set forth! in the specification and covered by hej laimsappe l ed e .Beferring. to the drawings-which illustrate one uerhhodiment of ny invention, and in which like, refere'ii'oe numerals indicate like parts:

eFist isenfisbme ri v w 0 efg et hlock,

1924. ser -gl 1N0. i724,9 e2.

showing the'top and side'whioh :arenorinally exposedtortheheat of the-fire.

,is a .si inil ar isometric view of the grLa-te block turned-upon its normally nnex posed side so as to show tlieexposed sideloi the block feswelbas the'bottoni thereof.

gFig; is across section on the line: 3-'+3 of F*l-g.;1.

:Fig. 14 is a cross section on the line #l-14= (if Eig. 1. v

\Fig.;-'5 is n side,eleWation-lorokenaWay to show ,-a side=b.ar.rwith a number of grate blocks mounted thereon.

V ,rFig. 6.is stop plan viewo'f oneset, oEEgrate blooks shown in Fig.

Fig. jisn fragmentary, detail; in horizontal e'etion so the. i v;7. 7 of {Fig -8 is-e side elevation, jisimila-r 3170 Fig. *5, trwnodi on- Fig-i i e *f QgmQ tiL W/SGG EI o theline 9 9 of Fig. 8 showing; the; tortuous air .pas-

sage. Y

fEig: 11 1 3: oss 'tionron t eiline .10;10 QfJFig- ;.2

V ig. llisaperspeetive View of the bloek hown fin-F g 1-8- (1, 1 cw d c ith my inven on, 1 -12 0- -ide a .tuyre;blook with n tortuous air pas sage; so constructed that the air is caused to i pre i Qtfi- Wit a ons de l surface of {thehlocknnd so {absorb heat therefrom, thus seryinggboth' to cool the block end -to P hea theiuyr .e r- 0, 1 pro d a qsklw h Pock t bni h upp e po e su ably the nose portion so that the cooling air may be fed into the fuel bed at the end of the block.

As will be apparent from inspection of Fig. 5, Fig. 10, and the patent to Riley, two series of grate blocks are mounted in step-like formation on two juxtaposed, inclined, reciprocable side bars 12 so as to form a tuyere wall and fuel supporting grate. It will be understood that the side bars incline downwardly from the upper front end of the stoker towards the ash dump and that the nose of the block is at the rear and faces the ash dump. The grate blocks have openings therethrough communicating with the space beneath the supporting side bar, and these openings connect with passages formed between the grate blocks in such a manner as to conduct air to the fuel bed through suitably located tuyere openings.

While this block may be constructed in various shapes and arrangements within the scope of my invention, the block as illustrated comprises a metal casting having a vertical side Wall 15 which contacts with a like wall on the adjacent block in the other series. A wall 16 parallel with the side wall extends throughout substantially half of the block at the end covered by the block above, and is connected to the wall 15 by struts or walls 17 and 18 to form a hollow opening through which air may pass upwardly from beneath the side bars. A flange 20 connected with the wall 16 serves to restrict the size of the vertical opening 21 between walls 15 an 16, and

in cooperation with the top of the wall 15 serves as a support for the block above.

Extending rearwardly fromthe wall 18 is a web 22 connected with the wall 15. In the form illustrated, the rear portion 23 of the web is substantially horizontal, the central part 24 is inclined at substantially the same angle as the rearward sloping portion 25 of the flange 20 and the forward portion 26 is substantially horizontal. As will be apparent from an inspection of Fig. 5, these grate bars are arranged one above the other with the web portions 23 and 24 exposed, and the web pgrtion 26 beneath the portion 23 of the block a ove. a

On the under side of the web '22 is a series of substantially parallel flanges which serve the double purpose of conducting heat away from the web portion and of forming a tortuous passage to maintain the circulating air in contact with the metal for aconsiderable length of time and thus absorb heat therefrom. The flanges 28 depending from web port-ions 24 and 26 are arranged and shaped to fit upon the flat portions 20 and 25 of the block beneath, but as will be observed by inspection of Fi 's. 2 and 3, the flanges do not extend all the way ,across the grate block but leave a space connecting with the opening 2 21 through the block beneath whereby air may be fed to the nose end of the block. Since the side wall 16 does not extend above the flange 20, 25 air will issue laterally through the tuyere openings 29 (Fig. 5) formed by the flanges 28, the same as shown in the Riley patent.

Flanges 30 are arranged on the under side of the nose portion 23 of the web and these are adapted to fit against the web portion 26 between the walls 15 and 16 of the block beneath. For this purpose the flanges 30 are made slightly shorter than the width of the block, as shown in Figs. 2, 4 and 7, and in order to provide a labyrinth for the circulation of air, these flanges are set in a staggered formation' and are arranged to be located above the web 26 of the block beneath, so that air may pass around the end of one and then to the opposite side of the block and around the end of another until it has reached the nose end of the block where it escapes through the opening 32 in the wall 33 which connects the walls 15 and 16 adjacent the nose end of the web portion 26 of the block beneath the labyrinth forming flanges. This opening 32 serves as a tuyere opening through V which air is admitted to the fuel supported above.

A set of transverse flanges or ribs 36 are arranged on the upper side of the web 22, the top of these ribs being preferably on a line with the top of the rearward portion of the wall 15. These ribs are arranged in this position in order to catch slag and ash that form during combustion of the fuel and to hold this dead matter in position on the grate blocks and thus furnish an additional insulating means which tends to prevent destruction of the block by heat and oxidation. At the extreme tip of the nose, a further set of flanges 37 may be run longitudinally of the block for strengthening purposes, but if desired a lateral flange may be employed at the nose to catch the slag there as Well as further up the block.

In accordance with the modification shown in Figs. 8, 9, and 11, I may extend the labyrinth forwardly as far as desired and thus.

provide for a longer contact of the circulating air with the block. As illustrated, the wall 38 corresponding with the wall 16 of Fig. 1 may be extended rearwardly to form a side wall above the flange portion 39 corresponding with part 25 (Fig. l) and fit against the bottom of the web and side wall of a block above. The labyrinth forming flanges 40 depend from the under side of the web il.

warms from the front to the rear are formed in the side wall 38 opposite the labyrinth and the flanges 40 may be so spaced as to form a gradually narrowing passage from front to rear. This insures a proper distribution of air to the side openings 44 and the rear opening 45 which corresponds with the opening 32 in Fig. i.

It will now be apparent that I have provided an effective means for preventing rapid destruction of a grate block by insulating the top from the fire and cooling the under portion. Also, I insure a proper feeding of air to the fuel bed both laterally and at the nose of the grate block. It will be evident from the above disclosure that various changes may be made in this construction without departing from the spirit and the scope of the appended claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is: 4

1. A grate block for a stoker comprising a substantially horizontal web, one end of which has spaced transverse ribs on its upper side arranged to catch ashes and hold the same in position against theaction of the fuel moving across the ribs lengthwise of the block and thereby form a heat insulating layer, and walls cooperating with the Web to form an air channel, said air channel serving when the blocks are piled with other blocks in a step-like formation to admit air to the fuel bed supported thereon.

2. A grate. block comprising-a unitary casting having a longitudinal web portion, a set ,of dependmg flanges on the underside thereof and upwardly projecting walls on its upper side, said block being so constructed that it may be piled with other blocks in step-like formation with the flanges on one block cooperating with the walls on another block to form a tortuous air passage and a tuyere to the fuel bed supported thereon.

3. A grate block for a stoker comprising a longitudinal web having ribs on the upper side of the rear portion thereof forming ash receiving pockets, flanges onthe under side of the web, and walls on the upper front portion so constructed that when assembled in a step-like formation two similar blocks will form a tortuous air channel therebetween, the walls at the front of the lower block defining an air inlet opening therethrough which. communicates with the tortuous channel and said block having a tuyere opening through which air may pass after traversing the tortuous channel in cooling contact with the flanges.

4. A grate block for stokers adapted to be piled with similar blocksin a step-like formation comprising a longitudinal web, a set of flanges on the under side thereof, and side walls cooperating with the web to form a tortuous air channel when the blocks are assembled in a stoker, said block being so shaped as to pro videtuiybre openings atzth e if'uel supporting-endiandi-tlrrouglrthesideflwallswhich communicate with wa'rious eportionsiof said tortuous air channel.

A stokericomprising' ':a side 'barand aseries of grate bloclzs mounted in step li ke formation thereon, a longitudinalwwe-beformingia tfuelsup-porting"portion'for :each block, flanges on the underside ofthe web and walls on rthe upper portion of .-the "block beneath, which forin 2Lt0l't1l0llS air.-:passage,and walls definingaaniair inlet and tuyere opening communicating with said passage,--xwhich :are so constructed and .arrangedrthat zliI' ,must PHESSJ'iIl cooling contact withaniextensive surfaceiarea of tlae block beforeissuing; through theituyere. opening.

-6. A Qs'tolier .conrprisi'ng a side bar and .a series *of grate ablocks mounted in :ste p alike formation thereon, eachi'block having walls defining an air :i-nletithrough ltSffOIWViflld gpdrtion, transverse ribs ontheifuel supporting portionofthe block to catchandjhold ashes thereon, flanges on the under side of the fuel supporting portion and walls on the block beneath which form an extensive air passage connecting with said inlet, and a tuyere opening from said passage adjacent the fuel supporting portion whereby air is caused to pass in cooling contact with a considerable surface of said block and become preheated before it issues into the fuel bed.

7 A stoker having in combination a side bar and a set of grate blocks mounted in step-like formation on said bar, each of said blocks being provided with transverse ribs on the fuel supporting portion to catch ashes and form a heat insulation for the block, a set of staggered flanges on the under side of said block, walls on the block beneath cooperating with said flanges to form a tortuous air passage, walls defining an air inlet to said passage, and a tuyere opening from said passage beneath the fuel supporting portion of each block, said parts being so arranged and constructed that air may pass upwardly through said inlet and thence through the passage in cooling contact with the flanges to the tuyere opening.

8. A stoker comprising aside bar and a series of grate blocks mounted in step-like formation thereon, the fuel supporting portion of each block having heat radiating flanges on its under side, walls on the block beneath which cooperate with said flanges to form a tortuous air passage and means defining an air inlet through the block opening into said passage and tuyere openings from said passage at the fuel supporting portion and side of the block which cause air to pass in contact with an extensive surface area of the block in traversing from the inlet to the tuyere openings.

9. A grate block for a stoker comprising a substantially horizontal web having at one end parallel flanges depending from its under side and parallel transversely arranged ash retaining ribs on its upper side, a vertical side Wall connected to the Web and the ribs, and Walls defining an opening through the block at the opposite end from the ribs and flanges.

10. A grate block for a stoker comprising a substantially horizontal web'having at one end a series of ribs on its upper side and parallel transversely arranged flange on its under side, a vertical side Wall connected to one side of the Web, and Walls defining an opening through the block, the Walls and flanges being so shaped that, When a series of blocks are piled in step-like formation, the flanges will cooperate with the opening through the block and the Walls to form lateral tuyeres and a tortuous air passage issuing near the end of the block.

Signed at Worcester, Massachusetts, this 28th day of June, 1924.

IRVING ALBERT TAYLOR. 

